Breakdown Limits on Gigavolt-per-Meter Electron-Beam-Driven Wakefields in Dielectric Structures

Abstract

First measurements of the breakdown threshold in a dielectric subjected to $\mathrm{GV}/\mathrm{m}$ wakefields produced by short (30–330 fs), 28.5 GeV electron bunches have been made. Fused silica tubes of $100\mu \mathrm{m}$ inner diameter were exposed to a range of bunch lengths, allowing surface dielectric fields up to $27\mathrm{GV}/\mathrm{m}$ to be generated. The onset of breakdown, detected through light emission from the tube ends, is observed to occur when the peak electric field at the dielectric surface reaches $13.8\pm 0.7\mathrm{GV}/\mathrm{m}$. The correlation of structure damage to beam-induced breakdown is established using an array of postexposure inspection techniques.